1. Field of the Invention
The present invention relates to an improvement of a lighting device used in an interior of a vehicle.
2. Description of the Related Art
There is a lighting device for an interior of a vehicle that emits light from a surface of a light guide plate to use it as a light source. For instance, in a structure disclosed in patent literature 1, a plurality of LED lamps are arranged so as to be opposed to one end face of the light guide plate to make the lights of the LED lamps incident on the light guide plate and take out the lights from a flat plate surface and emit the lights on the surface. The lighting state is controlled by a switch arranged on the interior side of the vehicle. In such a structure, an area near the LED lamps of a light emitting part excessively emits the light with high luminance, so that unevenness in luminance is outstanding. In order to prevent this phenomenon, for instance, in a structure disclosed in patent literature 2, an edge of a light emitting part side of a light guide plate (especially, a part near an incident part) is covered with a light shield sheet to prevent light from being radiated from the part near the incident part and cancel the unevenness in luminance. As the switch for controlling the lighting state of the above-described lighting device for the interior of the vehicle, a push type switch is widely used. As examples of the push type switch, patent literatures 3 and 4 are exemplified.    Patent Literature 1: JP-A-2004-322858    Patent Literature 2: JP-A-2000-127847    Patent Literature 3: JP-A-2006-196270    Patent Literature 4: JP-A-2007-184174
In the structure of the patent literature 1, since the switch is provided at a position separated from a light emitting part by considering a space in which the LED lamps are arranged, dullness is given to an observer and an outward appearance is not good. Further, in the structure disclosed in the patent literature 2, since the light shield sheet is provided, the switch is provided at a position more separated from a light emitting part. As a result, the dullness is more increased and the outward appearance is worse. In order to eliminate such dullness and improve the outward appearance, the switch may be provided at a part near the light emitting part. However, when the structure of the switch disclosed in the patent literatures 3 and 4 is directly applied, the device undesirably has its thickness increased and is enlarged.